Three wildfires ignited by lightning strikes were burning through timber, sagebrush and piñon-juniper forest across more than 10,900 acres in northwestern Colorado on Sunday, and federal authorities deployed more than 400 firefighters to contain the flames.

The newest fire broke out Saturday afternoon 15 miles south of Maybell. Dubbed the Pine Tree Fire by an interagency fire management team, it spread across more than 4,000 acres, the team’s spokesman, Chris Barth, said Sunday night. Flames forced the closure of Moffat County Road 57 from the intersection with U.S. 40 south into Rio Blanco County. Firefighters were mobilizing late Sunday to suppress this blaze.

“There are some ranches, different types of structures,” Barth said. “No reports of anything burned.”

Federal fire crews on Sunday also were posted on the 4,112-acre Deep Creek Fire, which started Sept. 4 northeast of Hayden. It will keep burning until Sept. 19, a firefighting bulletin said. Fire managers deemed this fire 62 percent contained.

It was burning at a moderate intensity with single trees occasionally igniting, the bulletin said.

On Sunday, firefighting crews — 293 firefighters overall — worked at reinforcing clearings around the northern and southern edges of the Deep Creek Fire. On Saturday, firefighters used aircraft to douse hot spots around edges and to search for new fires.

Fire managers said lightning strikes sparked both fires, as well as another another wildfire in northern Routt County, dubbed the Big Red Fire. It had burned an estimated 2,854 acres as of Sunday and was 20 percent contained.

“These are active suppression fires,” Barth said. “We’re looking to keep these fires as small as possible.”

The map shows all active and inactive wildfires in Colorado in 2017 according to InciWeb. Click a map marker for details. Locations are approximate; circle size is based on acres burned relative to other fires but is not location-accurate.

Bruce Finley covers environment issues, the land air and water struggles shaping Colorado and the West. Finley grew up in Colorado, graduated from Stanford, then earned masters degrees in international relations as a Fulbright scholar in Britain and in journalism at Northwestern. He is also a lawyer and previously handled international news with on-site reporting in 40 countries.

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